Present day airports, of whatever size, make use of numerous, often hundreds, of light fixtures for purposes of illumination of the edge of the airport runway, taxiway and parking areas to thereby minimize the possibility that an aircraft will inadvertently travel off the edge thereof. Such airport light fixtures involve considerable cost, both by way of initial capital investment, accidental breakage and maintenance in that the state-of-the-art runway light fixture is designed to withstand intense vibration and high wind velocity encountered in take-off and landing operations of jet aircraft, as well as bad weather. Such fixtures must, as well, remain operable over a broad range of environmental factors including heat, humidity, erosion, dust, wind, vegetation and insects. Accordingly, each runway light fixture represents a significant, but risk prone, capital asset of the airport. In order to protect this asset and to ensure maximum functionality, extensive use of mowing and other equipment is made to trim and limit the growth of grass and vegetation thereabout. However, such equipment may itself cause damage to runway lights. In many areas, it is also necessary to employ plant poisons and pesticides to protect runway lights from insects and the ingrowth of vegetation. Accordingly, the maintenance of runway lights entails not only the cost labor associated with continual trimming of vegetation but, as well, the potentially hazardous use of herbicides and pesticides to protect the light from vegetation, insects, and other small animals which might otherwise damage the runway lighting.
The prior art has addressed the above problem through the suggestion of complicated and expensive light fixtures or light fixture protectors and, inter alia is represented by U.S. Pat. No. 4,104,711 (1978) to Carter, entitled Airport Light Fixture; U.S. Pat. No. 5,122,798 (1992) to Kaolian, entitled Airport Ground Light Arrangement; U.S. Pat. No. 5,669,691 (1997) to Barrow, entitled Airport Runway or Taxiway Light Fixture; and U.S. Pat. No. 5,971,561 (1999) to Fitzwater, entitled Airport Field Light Protector.
All of the above solutions, while clearly useful in extending the life of airport runway light fixtures, provide no help in the above-described environmental problems associated with extensive groundwork and other maintenance directed to the vegetation which inevitably will try to envelop runway light fixtures. A recognition of such limitations in the prior art is reflected in Kaolian above which suggests the use of a semi-rigid disk shaped body formed of a weather-resistant material which comprises an integral part of the runway fixture per se. Therein, the disk requires excavation of earth and insertion of gravel under the disk. In other words, in systems such as Kaolian and Fitzwater above, a protective rigid or semi-rigid disk is essentially integrated as a part of the airport ground light unit. In such solutions, the outermost edge or periphery of such disk-like elements are susceptible to uplifting under the effect of jet blast, ambient wind, water, and the activity of insects and small animals even if the disk is positioned below ground level.
In addition, the structure of Fitzwater entirely enclosed the breakaway coupling of the light fixture, thereby negating its safety functions. That is, the fixture, in the invention as set forth below, if impacted by any part of an aircraft, will instantly break away and lie flat upon the ground. In Fitzwater, this will not occur.
Accordingly, none of the suggestions in the prior art which might, superficially, appear related to the present invention, are practical in terms of such long-term external effects thereupon. In addition, it is essential that any peripheral disk, skirt, or the like associated with a runway light be as flat as possible to minimize interference with, or damage to, lower blades of landscaping equipment, the use of which would remain necessary with respect to airport maintenance beyond the periphery of any system for the protection of airport runway light fixtures. It is further noted that the use of gravel to suppress foliage about landing strips has given rise to its own problems; for example, jet blast is capable of dislodging and blowing gravel about a taxiway thereby creating a hazard to other aircraft and to personnel in the area.
It is, thereby, to be appreciated that prior art attempts to suppress the growth of foliage and to control other factors impacting upon airport ground lights have been relatively ineffective and, as well, have proven costly in terms of manpower, maintenance and particularly the replacement of lights and other components of such ground light systems when damage thereto occurs.
The present invention thereby represents an effective alternative to such art as Kaolian and Fitzwater, referenced above.
With regard to U.S. Pat. No. 5,436,812 (1995) to Stewart, entitled Airport Marker System, the same teaches a generally conventional airport runway light fixture system including a metallic base plate and a concrete base thereabout of a type which it is an objective of the present system to entirely cover to thereby preclude encroachment of vegetation and insects upon the light fixture system, this is more fully set forth below.
The instant invention relates to a system for the protection of airport runway light fixtures having a co-axial, substantially ground level metallic support secured within a ground level and in-ground concrete base. The system more particularly comprises a flexible mat including an opening about a central axis thereof, said opening having a radius substantially equal to that of said metallic support from the vertical axis of said light fixture, said mat also having a plurality of peripherally located apertures. The system further includes a plurality of anchors for said mat, corresponding in number to the number of said apertures, each of said anchors comprising a planar head and, integral therewith, means for the penetration and engagement of the ground upon which said mat is to be positioned, said penetration means proportioned for complemental insertion through said peripheral apertures of said mat, wherein said heads of said anchors engage said mat when said penetration means are fully penetrated into the earth upon which said mat is to be secured. In a preferred embodiment, the upper surface of said planar head of each anchor comprises an axially disposed nut, Alan Head screw or the like proportioned for complemental engagement with a drive element of a power tool to thereby effect rotation of the anchor into the earth.
In view of the above, it is an object of the present invention to provide an improved system for the protection of airport runway light fixtures from airfield maintenance equipment, this inclusive of a protective mat therefore and method of efficient securement thereof to the area surrounding such runway and taxiway light fixtures.
It is another object of the invention to provide an airport ground lighting system having improved means for the suppression of foliage and pests thereabout.
It is a further object to provide a system of the above type which will reduce mowing presently associated with runway lighting and lighting fixtures.
It is a further object to provide an airport ground light system protection for reduction of soil erosion in the area about the fixture.
It is a yet further object of the invention to provide a means for the protection of airport runway light fixtures not susceptible to uplift under the influence of jet or propeller airblast.
It is still another object to provide an improved system to enhance the visibility of runway ground lights.
It is a still further object of the invention to provide a system for the protection of airport runway lights which will reduce the cost of labor associated with the use of herbicides and pesticides about said lights and will reduce risks to workers otherwise required to walk onto or near the airfield for such tasks.
It is a yet further object to provide a system of the above type which is fully compatible with all sizes and weights of lawn maintenance equipment and which will pose no risk to such equipment or to an aircraft that may inadvertently travel over such a system.
It is a still further object of the invention to provide a system of the above type which will, through the use of conventional portable power tools, can be quickly installed or repositioned.
It is a further object to provide a system of the above type which is essentially immovable after it has been properly secured about a runway light fixture or airport sign and into the earth.
The above and yet other objects and advantages of the present invention will become apparent from the hereinafter set forth Brief Description of the Drawings, Detailed Description of the Invention and Claims appended herewith.